Canterbury Northwester

A dry and warm, foehn type wind, generally northwest in direction ahead of an easterly travelling depression from the Tasman Sea. The winds can be hot and enervating over the Canterbury Plains of South Island, but following the passage of the depression the wind veers southwest, bringing cooler, moister polar air and temperatures fall.

Depressions to the south of Australia entrain hot air from the interior which become moisture laden on passage east across the Tasman Sea, depositing much of the moisture as precipitation over the Southern Alps on the western side before adiabatic warming and drying occur on the descent on the eastern side of the Southern Alps.